I have a femaoe miniature daschund. She is approximately 12 months old; she is an adopted pet, full blooded-no papers. She has been in heat already once since we got her at Easter 2007. How often can I expect her to come in heat?

For most females, it is twice a year. I can think of no good reason to put up with the flaky behavior, mess, efforts to get loose, risks of accidental breeding, cancer, etc. by not having her spayed. With no papers, breeding her will be an even bigger money loser. Call the vet tomorrow. Once the next heat cycle start, most vets won't want to spay her.